How to Link Consents — Base Consent ID (consentGroupId)
The Base Consent ID (consentGroupId) is a persistent reference that links related consents within a TPP's service. It allows a common identifier to persist across multiple consents that belong to the same logical group — initiated by the same user, for the same service. Used to enable a coherent presentation of consent within Consent Management Interfaces (CMIs).
The four scenarios for a Base Consent ID
Consent continuation
When a user's consent has expired (i.e. the ExpirationDateTime is in the past), but the user wishes to continue using the TPP's service, the TPP must create a new consent (with a new consentId) for the same permissions.
To maintain continuity, the TPP should set the original ConsentId as the BaseConsentId for the new consent.
If the original consent already had a BaseConsentId, the TPP must reuse that same BaseConsentId, not the immediate prior ConsentId. This ensures the entire chain of consents is consistently linked.
Consent re-establishment after revocation
If a user revokes consent and later wants to re-establish access to the TPP's services, the TPP should create a new consent with the same permissions.
As with consent continuation, the TPP should reference the original ConsentId as the BaseConsentId — or, if applicable, reuse the existing BaseConsentId — to maintain the logical association.
Consent update (permission expansion)
Suppose a user originally grants consent with specific permissions (e.g. ReadAccountsBasic, ReadAccountsDetail, ReadBalances), and the TPP later introduces new functionality (e.g. access to ReadDirectDebits). If the user opts in to this expanded scope, the TPP should:
- Create a new consent with the updated set of permissions
- Revoke the old consent
- Link the new consent to the original one by referencing the appropriate
BaseConsentId
User identity consistency
It is assumed that all consents linked via a BaseConsentId are associated with the same end user. Therefore, if during authentication the LFI determines that the userId associated with a newly submitted consent differs from the user who authorised the previous consent in the chain, the LFI should reject the new consent.
At a glance
| Scenario | Action |
|---|---|
| Consent expired, user continues service | Set original ConsentId as BaseConsentId |
| Consent revoked, user re-establishes access | Set original ConsentId (or existing BaseConsentId) as BaseConsentId |
| Permissions expanded | Create new consent, revoke old, link via BaseConsentId |
| User identity mismatch detected | LFI rejects the new consent |
Always trace back to the root ConsentId when setting BaseConsentId. Never use the most recent consent in a chain as the BaseConsentId if it already has one — doing so would break the link back to the original consent.